Buggy code:
@ Nullable @ Override public < T extends Enum > T getEnum ( @ Nonnull String name , @ Nonnull Class < T > enumType ) throws IllegalStateException , NoSuchElementException { } @ Nullable @ Override @ SuppressWarnings ( "unchecked" ) public < T extends Enum > T getEnum ( @ Nonnull String name , @ Nonnull T defaultValue ) throws IllegalStateException { } @ Nullable @ Override public < T extends Enum > T getEnum ( @ Nonnull String name , @ Nullable T defaultValue , @ Nonnull Class < T > enumType ) throws IllegalStateException { } @ Nullable @ Override public String [ ] getEnumArray ( @ Nonnull String name ) throws IllegalStateException , NoSuchElementException { } @ Nullable @ Override public String [ ] getEnumArray ( @ Nonnull String name , @ Nullable String [ ] defaultValue ) throws IllegalStateException , NoSuchElementException { } @ Nullable @ Override public < T extends Enum > T [ ] getEnumArray ( @ Nonnull String name , @ Nullable Class < T > enumType ) throws IllegalStateException , NoSuchElementException { } @ Nullable @ Override public < T extends Enum > T [ ] getEnumArray ( @ Nonnull String name , @ Nullable T [ ] defaultValue , @ Nonnull Class < T > enumType ) throws IllegalStateException { } @ Override public float getFloat ( @ Nonnull String name ) throws IllegalStateException , NoSuchElementException { } @ Override public float getFloat ( @ Nonnull String name , float defaultValue ) throws IllegalStateException { } @ Nullable @ Override public float [ ] getFloatArray ( @ Nonnull String name ) throws IllegalStateException , NoSuchElementException { } @ Nullable @ Override public float [ ] getFloatArray ( @ Nonnegative String name , @ Nullable float [ ] defaultValue ) throws IllegalStateException { } @ Override public int getInteger ( @ Nonnull String name ) throws IllegalStateException , NoSuchElementException { } @ Override public int getInteger ( @ Nonnull String name , int defaultValue ) throws IllegalStateException { } @ Nullable @ Override public int [ ] getIntegerArray ( @ Nonnull String name ) throws IllegalStateException , NoSuchElementException { } @ Nullable @ Override public int [ ] getIntegerArray ( @ Nonnull String name , @ Nullable int [ ] defaultValue ) throws IllegalStateException { } @ Nullable @ Override public String getString ( @ Nonnull String name ) throws IllegalStateException , NoSuchElementException { } @ Nullable @ Override public String getString ( @ Nonnegative String name , @ Nullable String defaultValue ) throws IllegalStateException { } @ Nullable @ Override public String [ ] getStringArray ( @ Nonnull String name ) throws IllegalStateException , NoSuchElementException { } @ Nullable @ Override public String [ ] getStringArray ( @ Nonnull String name , @ Nullable String [ ] defaultValue ) throws IllegalStateException { } @ Override public float getUnsignedFloat ( @ Nonnull String name ) throws IllegalStateException , NoSuchElementException { } @ Override public float getUnsignedFloat ( @ Nonnull String name , @ Nonnegative float defaultValue ) throws IllegalStateException { } @ Nullable @ Override public float [ ] getUnsignedFloatArray ( @ Nonnull String name ) throws IllegalStateException , NoSuchElementException { } @ Nullable @ Override public float [ ] getUnsignedFloatArray ( @ Nonnull String name , @ Nullable @ Nonnegative float [ ] defaultValue ) throws IllegalStateException { } @ Override public int getUnsignedInteger ( @ Nonnull String name ) throws IllegalStateException , NoSuchElementException { } @ Override public int getUnsignedInteger ( @ Nonnegative String name , @ Nonnegative int defaultValue ) throws IllegalStateException { } @ Nullable @ Override public int [ ] getUnsignedIntegerArray ( @ Nonnull String name ) throws IllegalStateException , NoSuchElementException { } @ Nullable @ Override public int [ ] getUnsignedIntegerArray ( @ Nonnull String name , @ Nullable @ Nonnegative int [ ] defaultValue ) throws IllegalStateException { } @ Nonnull @ Override public IObjectNode insertAfter ( @ Nonnull String after , @ Nonnull INode node ) throws NoSuchElementException { } @ Nonnull @ Override public IObjectNode insertAfter ( @ Nonnull INode after , @ Nonnull INode node ) throws NoSuchElementException { } @ Nonnull @ Override public IObjectNode insertBefore ( @ Nonnull String before , @ Nonnull INode node ) throws NoSuchElementException { int index = before . indexOf ( '.' ) ; if ( index != ( - 1 ) ) { IObjectNode closestNode = this . get ( before . substring ( 0 , index ) , IObjectNode . class ) ; <START_BUG> closestNode . insertAfter ( before . substring ( ( index + 1 ) ) , node ) ; <END_BUG> return this ; } return this . insertBefore ( this . get ( before ) , node ) ; } @ Nonnull @ Override public IObjectNode insertBefore ( @ Nonnull INode before , @ Nonnull INode node ) throws NoSuchElementException { } @ Override public boolean isNull ( @ Nonnull String name ) throws IllegalStateException , NoSuchElementException { } @ Override public boolean isPresent ( @ Nonnull String name ) { } @ Override public boolean isPresent ( @ Nonnull String name , @ Nonnull Class < ? extends INode > nodeType ) { } @ Nonnull @ Override public < T extends INode > Iterator < T > iterator ( @ Nonnull Class < T > nodeType ) { } @ Nonnull @ Override public IObjectNode remove ( @ Nonnull String name ) throws NoSuchElementException { } @ Nonnull @ Override public IObjectNode remove ( @ Nonnull INode node ) throws NoSuchElementException { } @ Nonnull @ Override public IObjectNode replace ( @ Nonnull String name , @ Nonnull INode replacement ) throws NoSuchElementException { } @ Nonnull @ Override public IObjectNode replace ( @ Nonnull INode node , @ Nonnull INode replacement ) throws NoSuchElementException { } @ Override public int size ( ) { } @ Nonnull @ Override public Stream < INode > stream ( ) { }

Fix:
closestNode . insertBefore ( before . substring ( ( index + 1 ) ) , node ) ;